CVE-2026-72686: Uncontrolled Recursion in Elasticsearch Leading to Denial of Service

Published Aug 13, 2026
·
Updated

A flaw in Elasticsearch allows a low-privileged authenticated user to submit a single request containing a crafted user-supplied input. A specific internal component validates the input using a recursive routine and applies no bound to the length of the value being validated, so the validation causes the thread to exhaust its stack. The resulting fatal error is not handled by the surrounding execution paths and terminates the affected node process, producing a denial of service.

Affected Software

4 affected components
Elasticsearch Elasticsearch
Elastic Elasticsearch>=8.0.0<8.19.20
Elastic Elasticsearch>=9.0.0<9.4.5
Elastic Elasticsearch>=9.5.0<9.5.1

Event History

Aug 13, 2026
CVE Published
via MITRE·07:10 PM
Data Sourced
via MITRE·07:10 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·08:17 PM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2026-72686?

The severity of CVE-2026-72686 is medium with a score of 6.5.

2

How does CVE-2026-72686 affect Elasticsearch?

CVE-2026-72686 allows a low-privileged authenticated user to perform denial of service attacks through uncontrolled recursion by submitting a crafted request.

3

Who is impacted by CVE-2026-72686?

CVE-2026-72686 affects instances of Elasticsearch where low-privileged authenticated users have access to submit requests.

4

How do I fix CVE-2026-72686?

To fix CVE-2026-72686, update to the latest version of Elasticsearch that addresses this vulnerability.

5

Can CVE-2026-72686 lead to data loss?

While CVE-2026-72686 can result in denial of service, it does not directly lead to data loss as it primarily affects availability.

Contact

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